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2解ï¼å
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f(x)=2^(-x)-1 (x<=0)
f(x)=f(x-1) (x>0)
å æ¤
f(x)=2*2^(-x)-1 (0,1] (xçåºé´)
f(x)=4*2^(-x)-1 (1,2]
f(x)=8*2^(-x)-1 (2,3]
f(x)=16*2^(-x)-1 (3,4]
......
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(2) (-â,0] å(1,2]ææ ¹ å aâ(-2,0)
(3) (0,1]å(1,2]ææ ¹ å aâ(-2,0)
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